1. Field of the Invention
The present invention relates to an optical connector, and in particular to an optical connector that connects together optical connector plugs inserted from the front and back of a backplane in a housing body installed by using an installation hole in the backplane of a plug-in unit, for example.
2. Description of the Related Art
What is termed a backplane connector (referred to hereinbelow as a xe2x80x9cBP connectorxe2x80x9d) is a plug-in type optical connector that connects optical connector plugs inserted into both the front and back of a backplane using a backplane housing (hereinbelow, a xe2x80x9cBH housingxe2x80x9d) assembled using an installation hole in the backplane of a plug-in unit, for example.
FIG. 46 is an example of this BP connector.
In FIG. 46, reference numeral 1 is a plug-in unit, reference numeral 2 is a printed board, reference numeral 3 is a backplane, reference numerals 4a and 4b are connector plugs (hereinbelow, xe2x80x9cMPO plugsxe2x80x9d), reference numeral 5 is a printed board housing (hereinbelow, xe2x80x9cPH housingxe2x80x9d), and reference numeral 6 is a BH housing.
The MPO connectors 4a and 4b are optical connectors specified in JIS C 5982 and IEC 1754-7, and having a structure that supports an optical connector ferrule 4c, whose end has been PC (Physical Contact) polished, in a plastic housing.
This BP connector is assembled by engaging a PH housing 5 in a BH housing 6 installed in a backplane on the side of a plug-in unit 1 by inserting a printed board 2 that anchors the PH housing 5 to the plug-in unit 1. The engaged PH housing 5 and the BH housing 6 form the optical connector adapter 7, and connect the MPO plugs 4a and 4b inserted from both sides. The MPO plug 4a, inserted into the optical adapter 7 from the PH housing 5, is inserted in advance into the PH housing 5, and at the same time that the printed board 2 is inserted into the plug-in unit 1, the optical connector adapter 7 is inserted. On the plug-in unit 1, a plurality of printed boards 2 can be accommodated in parallel at a high packing density, and thus high-density packing of optical connector adapters 7 is possible with this BP connector
FIG. 47 is an exploded perspective drawing showing the BH housing 6.
As shown in FIG. 47, the BH housing 6 provides a housing body 8 and a backside housing 9 that are disposed opposite each other via the backplane 3. The housing 8 is disposed on the printed board 2 side (the left side in FIG. 7), and the backside housing 9 is disposed at a position facing the housing body 8 via the backplane 3. Pins 10 project from the housing body 8, pass through to the opposite side of the backplane 3 by being inserted through the installation hole 11 in the backplane 3, and anchor the backside housing 9 to the protruding ends of the pins 10 by screws 12.
FIG. 48 shows the installation hole 11.
As shown in FIG. 8, the installation hole 11 is rectangular, and has an extended part 13 in the four corners. The pins 10 are accommodated in the opposing pairs of extended parts 13 and 13 along the diagonal (omitted from figure) of the installation holes 11, and furthermore, in the vertical direction (top to bottom in FIG. 48), a gap 14 of approximately a=1.60 mm is maintained, and in the horizontal direction (left to right in FIG. 48), a gap 15 of approximately b=0.34 mm is maintained. The housing body 8 and the backside housing 9 slidably hold the backplane 3, and thus the BH housing 6 can float within the range of movement of the pins 10 and 10 in the gaps 14, 15. Thereby, as shown in FIG. 46, when the PH housing 5 is engaged in the BH housing 6 the size discrepancy is offset by the floating of the BH housing 6, and thus the engagement operability is improved.
Specifically, in the abutment connection between the optical connector ferrules 4c, 4d defined in JIS C 5981, one optical connector ferrule 4c is engaged in advance, the guide pins 4p projecting from the junction end are inserted and engaged in the guide pin holes 4q bored into the other optical connector ferrule 4c, and thereby precisely positioned. When the PH housing 5 has been properly engaged, the guide pins 4p can be smoothly engaged in the guide pin holes 4q due to the floating of the BH housing 6.
However, in the case of this BP connector, the dimension of the screw 12 diameter is about 1.2 mm, labor is involved in anchoring the backside housing 9 with a hand tool, and thus its operability is not satisfactory. In particular, when applying this BP connector to the wall of a building, etc., there are many cases in which an adequate work space cannot be secured, and this problem of operability becomes even more serious. In addition, because the screw 12 itself is a special order item, cost reductions are difficult, and at the same time, because the pin 10 and screw hole 16 (refer to FIG. 47) are formed conforming to the screw 12, there is the problem that labor is involved in their manufacture. Furthermore, because the installation hole 11 formed in the backplane 3 acquires a complicated shape corresponding to the screws 12, there is the problem that labor is involved in the formation of this installation hole 11. If the floating range of the BH housing 6 is too big or too small, ensuring the engagement of the PH housing 5 is difficult, and thus even more care is required in the formation of the screw 12, the pin 10, and the installation hole 11, which involves labor.
In consideration of the above, it is an object of the present invention to provide an optical connector that can be assembled simply, and furthermore does not require screws for anchoring, and makes possible the reduction of cost by reducing the number of parts by engaging flexible claws projecting from an anchoring part disposed opposite a housing body via the backplane in this housing body via an installation hole in this backplane, or engaging flexible claws projecting from an installation part attached to the outside of the housing body on this backplane via the installation hole.
The present invention is an optical connector providing a housing body and a fixed part that are disposed on opposite sides of the backplane, and installed so as to hold this backplane, and via an installation hole in the backplane, connect an optical connector plug inserted in the housing body and a separate optical connector plug inserted into the housing body from the direction opposite to this optical connector plug, and wherein this fixed part provides a plug insertion hole in which this optical connector plug is inserted, and flexible claws that engage by being disposed on opposite sides of the plug insertion hole and then inserted into the housing body. These flexible claws are installed so that the housing body and the fixed part hold the backplane by being engaged in the housing body via the installation hole in the backplane. In addition, the plug insertion hole communicates with the installation hole and the housing body to form a means to solve the above-described problems.
This optical connector is installed by holding the backplane between the housing body and the fixed part by engaging the flexible claws of the fixed part in the housing body via an installation hole in the backplane. In addition, the flexible claws can be structured so as to be detachable from the housing body, and thereby the removal operability is improved.
For example, as disclosed in the description of related art, in consideration of the structure in which a printed board housing attached to a printed board inserted in a plug-in unit is engaged in a housing body, the housing body is allowed to float. When the desired floating range is reliably attained for the housing body, the misalignment can be offset by the floating range of the housing body when the print port housing is engaged in the housing body, and thus the engagement operability is improved.
Thus, in the present invention, in order to attain reliably the desired floating range for the housing body, as recited in claim 2, a structure is generally adopted that permits displacement of the flexible claw in the installation hole by securing a clearance in the vicinity of the flexible claws inserted in the installation hole by a structure wherein the flexible claws of the fixed part passe through the installation hole in the backplane and is engaged in the housing body. According to this structure, the housing body and the fixed part, which are assembled by enclosing the backplane by the engagement of the flexible claw, form a backplane housing that can integrally float within the range of movement of the flexible claw in the installation hole. Therefore, by simply setting the range of movement of the flexible claw in the installation hole, the amount of floating of the backplane housing can be easily set, and the desired floating range or amount of floating in the housing body can be reliably attained. Thereby, in order to set the floating range or amount of floating of the housing body, it is unnecessary to prepare separately a special order part, and the cost can be reduced.
In addition, with the present invention, a structure can also be used wherein the housing body is supported at the desired position in the backplane by the pair of flexible claws, projecting from the installation part mounted and anchored outside the housing body, engaging the backplane on both sides of this engaging hole by passing them through the installation hole in the backplane, and holding the backplane between the pair of flexible claws and the supporting wall provided on the installation part.
In this structure, the backplane housing that comprises the housing body and the installation part is supported by both the outside and inside of the backplane. Moreover, due to the clearance guaranteed in the vicinity of the flexible claws inserted in the installation hole, the point that the desired floating range and the amount of floating of the housing can be easily and reliably attained, and the point that the desired floating range and amount of floating can be set without special order parts, are the same as described above.
Moreover, below, backplane connector is abbreviated xe2x80x9cBP connectorxe2x80x9d, backplane housing is abbreviated xe2x80x9cBH housingxe2x80x9d, and printed board housing is abbreviated xe2x80x9cPH housingxe2x80x9d.